Desmos is a graphing web-app that connects browser-based and mobile versions (Apple & Android) so that kids and teachers can learn using graphing functions on nearly any platform. Desmos’ cross-platform functionality makes it perfect for BYOD situations, and the quality of Desmos means that any 1-to-1 program will benefit from it. For math teachers Desmos has a large number of activities ready for use, and you can build and save your own activities as well. These activities are directly translatable to classroom use, so there is little prep involved. One example of Desmos’ user-friendly materials is Marbleslides, a parabola challenge that is available to all teachers who sign up for the (free) Desmos account.